Long-term farming systems experiments support barley as a profitable inclusion in canola and wheat rotations

Barley – and crop rotations that include barley – have proven profitable in southern New South Wales farming systems experiments.

CSIRO Agriculture and Food chief research scientist Dr John Kirkegaard says growers nominated crop sequences comprising canola/wheat/barley as a typical baseline farming system.

“The baseline was tested at all sites against other farming systems,” Dr Kirkegaard says. “It was most profitable at Wagga Wagga (Table 1) and in the top three farming systems at Condobolin. As a crop, barley performed well compared to wheat overall.”

Figure 1: Southern NSW farming systems project locations.

Long-term research

Dr Kirkegaard leads the southern NSW farming systems project, which is now in its eighth year. GRDC, CSIRO and the NSW Department of Primary Industries and Regional Development (DPIRD) are co-investors.

The small-plot-replicated research explores how to more efficiently convert rainfall into added profit across entire cropping sequences while managing soil fertility, weeds, diseases and costs.

He says the results made him wonder why barley is not grown more widely.

The key strategies being examined are:

• increased crop diversity (with legume options);
• nitrogen fertiliser management (conservative versus robust); and
• earlier sown systems (grazed and ungrazed).

Table 1: Farming systems for comparison.

Source: Dr John Kirkegaard, CSIRO Agriculture and Food

Overall results

Dr Kirkegaard says that barley had higher yields than wheat in individual years when similar soil nitrogen was available at sowing.

“Barley also had similar yields to wheat despite higher pre-sowing nitrogen for wheat,” he says. “These differences arose because wheat followed canola in the sequences, while barley followed wheat.”

The researchers sowed the barley varieties RGT Planet, La Trobe, Maximus CL and Neo CL in the experiments.

Wagga Wagga barley

On average, at the crop level, barley yielded more grain (six tonnes per hectare) than wheat (5.1t/ha) at Wagga Wagga (baseline system, Table 2).

Barley grown in the baseline canola/wheat/barley sequence also yielded more grain (6t/ha) than wheat grown in the intense baseline canola/wheat rotation (4.8t/ha), and the diverse lupin/canola/wheat (4.7t/ha) farming system (Table 2).

“It wasn’t as if we couldn’t grow a high-yielding wheat crop,” Dr Kirkegaard says. “For example, in 2021, RockStar wheat sown on 18 May yielded 6.9t/ha, which was lower than the La Trobe barley sown on the same date, which yielded 7.6t/ha.”

He says barley grown at Wagga Wagga made malt in four out of the six seasons. “At the crop level, barley grown in the baseline canola/wheat/barley sequence achieved an average gross margin of $1084/ha across the years at Wagga Wagga. This was higher than wheat ($730/ha) grown in the intense baseline system (canola/wheat) and wheat grown in the diverse lupin/canola/wheat rotation ($721/ha).”

Table 2: Performance at the crop level (barley versus wheat) at  Wagga Wagga (2018–23).

Source: Dr John Kirkegaard, CSIRO Agriculture and Food

Urana barley

Dr Kirkegaard says, on average, barley at Urana yielded 6.2t/ha of grain at the crop level (Table 3), higher than the 4.9t/ha of wheat when grown in a canola/wheat/barley sequence.

“Barley grown in a canola/wheat/barley sequence also yielded higher than wheat (5t/ha) grown in the intense canola/wheat system and diverse lupin/canola/wheat (5t/ha) system,” he says.

“In terms of profit, barley in the canola/wheat/barley system produced a $1085/ha margin, higher than wheat in the same sequence at $881/ha, and the return from wheat ($939/ha) grown in the diverse faba bean/canola/wheat system.”

As an example of barley yield at Urana in 2023, he says Maximus barley, sown at Urana on 11 May, produced 7.3t/ha of grain, while LRPB Raider wheat yielded 6.1t/ha.

Dr Kirkegaard says the barley grown at Urana achieved malting in three out of five seasons.

“At the crop level, barley grown in the baseline canola/wheat/barley sequence achieved an average gross margin of $1085/ha across the years at Urana, significantly higher than wheat at $881/ha.

“The barley gross margin in the baseline canola/wheat/barley was also higher than wheat ($730/ha) at Urana grown in the intense baseline canola/wheat system ($888/ha) and wheat grown in the diverse lupin/canola/wheat rotation ($721/ha).”

Table 3: Performance at the crop level (barley versus wheat) at  Urana (2018–23).

Source: Dr John Kirkegaard, CSIRO Agriculture and Food

Condobolin barley

At Condobolin, when barley was compared with wheat at the crop level, barley yielded 4.2t/ha and wheat 4.1t/ha in the baseline canola/wheat/barley farming system (Table 4).

Dr Kirkegaard says the average barley yield of 4.2t/ha was higher than the wheat yield and more profitable than the wheat grown in the canola/wheat/barley sequence and the canola/wheat farming system. It was also more profitable than the wheat grown in the lupin/canola/wheat sequence.

As an example of how well barley yielded in 2021 at Condobolin, he says La Trobe barley sown on 10 May yielded 7.3t/ha of grain, whereas RockStar wheat yielded 6.9t/ha.

Dr Kirkegaard says the Condobolin barley made the malt in five of the six seasons.

“At the crop level, barley in the canola/wheat/barley sequence was more profitable ($818/ha) than wheat ($752/ha),” he says.

“Barley in the canola/wheat/barley sequence was also more profitable than wheat ($752/ha) in the intense canola/wheat sequence and wheat ($782/ha) in the diverse lupin/canola/wheat sequence.”

Table 4: Performance at the crop level (barley versus wheat) at  Condobolin (2018–23).

Source: Dr John Kirkegaard, CSIRO Agriculture and Food

Systems performance

At the farming systems level at Wagga Wagga, Dr Kirkegaard says the results showed the canola/wheat/barley sequence with decile 7 nitrogen ranked first for profit with an average annual gross margin of $922/ha (Table 5).

“At Urana, the canola/wheat/barley farming system ranked fifth, producing an average profit of $813/ha over six years,” he says.

“The diverse faba bean/canola/wheat sequence ranked first with a $991/ha return over six years.”

He says that at Condobolin, canola/wheat/barley ranked third, with a $781/ha margin, higher than the diverse lupin/canola/wheat system.

“The canola/wheat/barley was outperformed by the intense canola/wheat system, which produced a $826/ha margin and ranked first.”

Table 5: Average gross margins ($/ha/year) and system water use efficiency  for timely sown grain-only systems at four sites over six years (2018–23).

Source: Dr John Kirkegaard, CSIRO Agriculture and Food

Crop choice

Dr Kirkegaard says he understands that storage, logistics, marketing and weed management all affect whether individuals decide to grow barley.

“We know barley doesn’t like acid soil, but if that problem has been fixed, our trials show barley can be a profitable choice,” he says.

“If weed management is influencing your decision, the results of a previous trial show that annual ryegrass can be managed cost-effectively in a diverse vetch hay/canola (triazine tolerant)/wheat/barley sequence.”

More information: John Kirkegaard, john.kirkegaard@csiro.au

Read also: GroundCover stories – Diversity is a defence against weeds and Farming systems trials go paddock-scale.